Weather in New Orleans in September

Shoulder season. September is shoulder season in New Orleans — cheaper, quieter, and a genuine gamble. Highs average 29.3 °C, lows 24.3 °C, and rain falls on 14 days — nothing in the month is working against you.

September ranks 9 of 12 in New Orleans: past the worst of the year but short of November, which is the month to book if the dates are open.

Rain on 14 days, 3 of them heavy. Enough to need a plan B, not enough to need a plan around it. Pack for 29.3 °C days and 24.3 °C nights; the spread matters more here than any single number.

What the averages hide

Averages flatten a month, and this one hides a few things: 11 days top 30 °C — hot spells arrive, but they break; the day barely swings — 5 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest September day reached 33.9 °C and the coldest night fell to 14.7 °C, and the wettest single day dropped 129 mm — roughly 100% of the month's rain in one day.

September is moderately variable: 25 mm in the driest year against 342 mm in the wettest, around an average of 129 mm. Roughly two Septembers in three land near that average, and the third does something else entirely.

Wind is light at 10.9 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 78%, high enough to notice on the warm days without dominating them.

How September sits in the year

Temperatures hold steady either side: 30.7 °C in August, 29.3 here, 25.5 in October. Nothing about the timing within the month matters much. Rain is the thing that moves: October brings 5 days less of it, so pushing the dates later buys drier weather.

Daylight in September

12.4 hours of daylight, losing 0.9 hours across the month. That is between New Orleans's extremes of 14.1 and 10.2 hours, so days are long enough not to constrain the plan.

An inland climate

Despite being inland, the year stays fairly even: 22.3 °C between the year's warmest afternoons and coldest nights.

How busy it gets

Quiet. Few other visitors, cheaper rooms, and a real chance some seasonal operators are shut.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

September in New Orleans versus nearby

If New Orleans is one option among several, the nearby comparison is worth making. Baton Rouge is close enough to be a coin toss — within a degree on temperature, 1 day less rain. Mobile is close enough to be a coin toss — within a degree on temperature, the same number of rain days.

So: September is a compromise. November is 20 points better and is what New Orleans is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in New Orleans

See all twelve months in New Orleans, or where else to go in September.